Python findModInverse Examples

Example #1

File: elgamal_key_generator.py Project: iso12/python

def generate(KeySize):
    print("Generating prime p...")
    p = rabinMiller.genrateLargePrime(keySize)
    e_1 = primitiveRoot(p)
    d = random.randrange(3, g)
    e_2 = cryptoMath.findModInverse(pow(e_1, d, p), p)

    publicKey = (KeySize, e_1, e_2, p)
    privateKey = (KeySize, d)

    return publicKey, privateKey

Example #2

File: elgamal_key_generator.py Project: Differlong/python

def generateKey(keySize):
    print('Generating prime p...')
    p = rabinMiller.generateLargePrime(keySize)  # select large prime number.
    e_1 = primitiveRoot(p)  # one primitive root on modulo p.
    d = random.randrange(3, p)  # private_key -> have to be greater than 2 for safety.
    e_2 = cryptoMath.findModInverse(pow(e_1, d, p), p)

    publicKey = (keySize, e_1, e_2, p)
    privateKey = (keySize, d)

    return publicKey, privateKey

Example #3

File: elgamal_key_generator.py Project: Parthi10/Py-Algorithms

def generateKey(keySize):
    print('Generating prime p...')
    p = rabinMiller.generateLargePrime(keySize)  # select large prime number.
    e_1 = primitiveRoot(p)  # one primitive root on modulo p.
    d = random.randrange(
        3, p)  # private_key -> have to be greater than 2 for safety.
    e_2 = cryptoMath.findModInverse(pow(e_1, d, p), p)

    publicKey = (keySize, e_1, e_2, p)
    privateKey = (keySize, d)

    return publicKey, privateKey

Example #4

File: affine_cipher.py Project: H-Darji/Hacking-Ciphers

def decryptMessage(key, message):
    keyA, keyB = getKeyParts(key)
    checkKeys(keyA, keyB, 'decrypt')
    plainText = ''
    modInverseOfkeyA = cryptoMath.findModInverse(keyA, len(SYMBOLS))
    for symbol in message:
        if symbol in SYMBOLS:
            symIndex = SYMBOLS.find(symbol)
            plainText += SYMBOLS[(symIndex - keyB) * modInverseOfkeyA % len(SYMBOLS)]
        else:
            plainText += symbol
    return plainText

Example #5

def decryptMessage(key, message):
    '''
    >>> decryptMessage(4545, 'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF{xIp~{HL}Gi')
    'The affine cipher is a type of monoalphabetic substitution cipher.'
    '''
    keyA, keyB = getKeyParts(key)
    checkKeys(keyA, keyB, 'decrypt')
    plainText = ''
    modInverseOfkeyA = cryptoMath.findModInverse(keyA, len(SYMBOLS))
    for symbol in message:
        if symbol in SYMBOLS:
            symIndex = SYMBOLS.find(symbol)
            plainText += SYMBOLS[(symIndex - keyB) * modInverseOfkeyA % len(SYMBOLS)]
        else:
            plainText += symbol
    return plainText

Example #6

File: affine_cipher.py Project: Prakash2403/Python

def decryptMessage(key, message):
    '''
    >>> decryptMessage(4545, 'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF{xIp~{HL}Gi')
    'The affine cipher is a type of monoalphabetic substitution cipher.'
    '''
    keyA, keyB = getKeyParts(key)
    checkKeys(keyA, keyB, 'decrypt')
    plainText = ''
    modInverseOfkeyA = cryptoMath.findModInverse(keyA, len(SYMBOLS))
    for symbol in message:
        if symbol in SYMBOLS:
            symIndex = SYMBOLS.find(symbol)
            plainText += SYMBOLS[(symIndex - keyB) * modInverseOfkeyA % len(SYMBOLS)]
        else:
            plainText += symbol
    return plainText

Example #7

File: affine_cipher.py Project: AmanSingh0-0/Python-Algos-MIT

def decrypt_message(key: int, message: str) -> str:
    """
    >>> decrypt_message(4545, 'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF'
    ...                       '{xIp~{HL}Gi')
    'The affine cipher is a type of monoalphabetic substitution cipher.'
    """
    keyA, keyB = divmod(key, len(SYMBOLS))
    check_keys(keyA, keyB, "decrypt")
    plainText = ""
    modInverseOfkeyA = cryptomath.findModInverse(keyA, len(SYMBOLS))
    for symbol in message:
        if symbol in SYMBOLS:
            symIndex = SYMBOLS.find(symbol)
            plainText += SYMBOLS[(symIndex - keyB) * modInverseOfkeyA % len(SYMBOLS)]
        else:
            plainText += symbol
    return plainText

Example #8

def generateKey(keySize):
    print('Generating prime p...')
    p = rabinMiller.generateLargePrime(keySize)
    print('Generating prime q...')
    q = rabinMiller.generateLargePrime(keySize)
    n = p * q

    print('Generating e that is relatively prime to (p - 1) * (q - 1)...')
    while True:
        e = random.randrange(2 ** (keySize - 1), 2 ** (keySize))
        if cryptoMath.gcd(e, (p - 1) * (q - 1)) == 1:
            break

    print('Calculating d that is mod inverse of e...')
    d = cryptoMath.findModInverse(e, (p - 1) * (q - 1))

    publicKey = (n, e)
    privateKey = (n, d)
    return (publicKey, privateKey)

Example #9

File: rsa_key_generator.py Project: Prakash2403/Python

def generateKey(keySize):
    print('Generating prime p...')
    p = rabinMiller.generateLargePrime(keySize)
    print('Generating prime q...')
    q = rabinMiller.generateLargePrime(keySize)
    n = p * q

    print('Generating e that is relatively prime to (p - 1) * (q - 1)...')
    while True:
        e = random.randrange(2 ** (keySize - 1), 2 ** (keySize))
        if cryptoMath.gcd(e, (p - 1) * (q - 1)) == 1:
            break

    print('Calculating d that is mod inverse of e...')
    d = cryptoMath.findModInverse(e, (p - 1) * (q - 1))

    publicKey = (n, e)
    privateKey = (n, d)
    return (publicKey, privateKey)